Warp slackening device



1950 w. c. ANGUS ETAL 2,515,339

WARP SLACKENING DEVICE Filed Nov. 6, 1946 By Ifl YLDE Patented July 18, 1950 2,515,389 WARP SLACKENING DEVICE William Campbell Angus and Joseph Rowland Wylde, Spondon, near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware Application November 6, 1946, Serial No. 708,016 In Great Britain November 23, 1945 2 Claims. 1

This invention relates to looms for weaving and is particularly concerned with stop motions in looms for preventing warp breakages in the event of the loom shuttle failing to enter the shuttle box on being picked across the loom, and being forced into engagement with the warp threads by the reed.

.A common form of loom stop motion for this purpose comprises a swell finger in each shuttle box, both secured to a catch rod extendin completely across the loom and mounted on the sley below and behind the shuttle boxes. The swell fingers are adapted to be engaged and pushed back by the shuttle when it enters the shuttle box, so rotating the catch rod slightly. Extended horizontally forward from the catch rod is a dagger adapted in its lower position to engage a knock-off block on the loom frame as the sley comes forward to beat-up, and to stop the loom. The engagement of the swell finger by the shuttle however, and the consequent rotation of the catch rod, lifts the knock-off dagger so that it passes over the knock-off block as the sley completes its forward movement. This device efiectively stops the loom, in the event of the shuttle being trapped in the shed, before the sley has reached its forward position. Its action, however, is apt to be too late for the risk of damage to the warps to be entirely eliminated,

and this is especially the case when the warp yarns being woven are of low extensibility. It is not conveniently possible to make the stop motion act earlier in the loom cycle without substantially redesigning the timing of the loom in such a way that the quality of the fabric produced would be detrimentally aifected. It is the object of the present invention to provide means for preventing warp damage when a shuttle fails to enter the shuttle box by stopping the loom and simultaneously or slightly previously slackening the warps.

According to the present invention a loom for weaving comprises a back rest over which the warps pass and by which they are deflected on their way from the warp beam to the fell of the fabric, means for stopping the loom on failure of the shuttle to enter a shuttle box, and means in association with said stopping means for moving said back rest so as to slacken the warps. By these means although the stopping of the 100m may not be effected till after the shed is so reduced in section that the warps are liable to be damaged by the shuttle, the slackening of the warps brought about by the movement of the back rest prevents such damage.

The means for stopping the loom on failure of the shuttle box may conveniently be of standard type, modified so as to effect the movement of the back rest. Thus the catch rod may carry an escape catch in the form of a horizontal lever extending towards the rear of the loom and having a hooked end which, when the dagger is in position to engage the knock-off block, is in a position to engage with a hooked rod extending to the rear of the loom to effect a lowering of the back rest. If it is more convenient for the horizontal rod. operating the back rest to beat a different level from the catch rod, the escape latch may be in the form of an auxiliary lever pivoted to the sley at a lower level than the catch rod and connected by means of a link to a lever extending rearwards from the catch rod.

By way of example, two forms of loom stop motion in accordance with the present invention will now be described, in their application to a loom, with reference to the accompanying drawings in which:

Figure 1 is a side elevation of a loom fitted with one form of stop motion;

Figure 2 shows the stop motion of claim 1 in operation; and

Figure 3 shows an alternative form of stop motion.

In the loom shown in Figure 1, the loom frame is indicated at 4, the sley at 5 and the shuttle box at G. The warp threads 1 are drawn from a beam 8 mounted low down at'the back of the loom and pass over the back-rest roller 9 on their way to the fell of the fabric ID. A swell H, extending through the back of the shuttle box 6, is engaged by a swell finger l2 mounted on a catch rod l3 extending across the loom and common to both shuttle boxes. Fixed to and extending forwards from the catch rod I3 is a dagger II which, when the shuttle fails to enter either shuttle box 6, is adapted to engage a knockoff block l5 and stop the loom. When, however, the shuttle enters either shuttle box, it displaces the swell II' and, through the swell finger l2, rocks the catch rod l3 and lifts the point of the dagger ll so that it passes over the knock-off block IS.

The mechanism described above is of a known type, and use is made of it for the purposes of the present invention. For this purpose, secured to the catch rod I3 is a rearwardly extending lever I! connected by means of a link I 8 to a hooked lever l9 pivoted at 20 to the sley 5. Above the hooked end of the lever I9 is a rod 2| mounted in slide bearings 22 on the inside of the loom frame and hooked at its forward end so as to co-operate with the hooked end of the lever l9. When the swell finger l2 and dagger l4 are in the stop position through the absence of the shuttle from both shuttle-boxes, the lever I9 is a projecting part 21 of a lever 28. The rod 2| passes through the lever 28 and engages it through spring buifers 29. In consequence, when the lever |9 engages and pulls forward the rod 2|, as shown in Figure 2, the lever 28 is pulled forward so as to release the lever 24 which in turn swings forward carrying the back-rest roller 9 until the lug 26 engages an adjustable stop 30. Thus, when the loom is stopped by the trapping of a shuttle in the shed, the warps I are at the same time slackened by moving the back-rest roller 9 forwards and downwards as shown in Figure 2.

When the fault is rectified the levers 24 on each side of the loom are restored to their original position by means of the handles 3| thereon, the lever 28 being provided with a return spring 32 which causes it to lock the lever 24 in its normal position. On restarting in this way it is generally desirable to release the fabric take-up (indicated at 33) by an amount depending upon the particular conditions of weaving; a distance equivalent to about two picks is generally sufllcient.

In the form of stop motion shown in Figure 3 the back-rest roller 9 is carried in a block 35 mounted in vertical slides 36 and held in a raised position by means of wedges 31 resting on brackets 38 on'each side of the loom. Attached to. the catch rod I3 is a rearwardly extending hooked lever 39 adapted to co-operate with a hooked rod 40 connected to the wedge 31 through a lever 4| and link 42. The lever 42 is pivoted on a bracket 43 on the loom frame. When the catch rod I3 is in the stop position the lever 39 e gages and pulls forward the lever 40 so that the wedge 31 is pushed rearwardly through the lever 4| and link 42 and the blocks 35 carrying the back-rest roller 9 are permitted to drop so as to slacken the warps I. The lever 4| is loaded by means Of a spring 44, so that, when the fault is corrected and the blocks 35 on each side of the loom are raised, the wedge 31 and lever 40 return to their normal position. The fabric take-up 33 is then adjusted, and weaving can be resumed.

Having described our invention, what we desire to secure by Letters Patent is:

l. A loom for weaving comprising a back-rest for the deflection and guiding of the warps on their way from the warp beam to the fell of the fabric, a horizontally movable wedge adapted to maintain said back-rest in a raised position, means for stopping the loom upon failure of the shuttle to enter a shuttle box, and means in association with said stopping means for displacing said wedge horizontally so as to release said backrest and slacken the warps.

2. A loom for weaving comprising a back-rest for the deflection and guiding 0f the warps on their way from the warp beam to the fell of the fabric, a horizontally movable wedge adapted to maintain said back-rest in a raised position, a shuttle-box swell, a swell finger and catch rod carried by the sley of the loom and adapted to be rocked by engagement with said swell, a hooked lever fixed to said catch rod, and a hooked rod extending to the rear of the loom and connected to said wedge, said hooked lever being adapted, on failure of the shuttle to enter a shuttle box, to engage said hooked rod on the forward motion of the sley and to displace said wedge horizontally so as to release said back-rest and slacken the warps.

WILLIAM CAMPBELL ANGUS. JOSEPH ROWLAND WYLDE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 507,328 Rigby Oct. 24, 1893 681,373 Phelps Aug. 27,1901

1,532,668 Baker Apr. 7, 1925 1,603,708 Northrop Oct. 19,1926

2,076,345 Marsden Apr. 6, 1937 FOREIGN PATENTS Number Country Date 555,678 France Mar. 28, 1923 

